ECN Forum Forums Code Related Discussion NEC & other Code issues Rain Tight EMT connectors.

We did a job replacing a ton of conduit on a buildings roof a couple years back. Inspector tagged us for not using the newly approved RT connectors. We ordered some and redid all the work. He then retags us saying his town only allows one manufacture of RT fittings. So we redid the work again =\

Now there are several manufactures that inspectors around here will accept, was just a fustrating learning process for us.

You can tell the difference between the fittings, the approved ones have colored plastic bushings everywhere. Also you can tell the difference when you get the price for the new ones

Shhh resqcapt19, don't give UL any ideas! They might remove rigid's aproval as RT!

Don,
My rigid connections are greased, and tight, bone dry in there. Some grease, Corroision-X, or Noalox and a 2' handle chain wrench will help to get it tight enough to run gas through, not that you would.

Just thought of something, do they make "New" Treadless RMC connectors and couplings with gaskets on them too?

What does a rain tight MC fitting look like? How do you keep the water out of the MC cable?

gfretwell, RMC/Rigid Metalic Conduit, there was an "R" in there.... If thats what you mean?

No not RMC, MC.
MC cable is usually labelled wet or dry. What type of connector do you use if you are a fanatic about the rain tight thing?

MC in the rain.......... Sounds like a bad idea.

You may not like it but
330.10(A)(12) In wet locations where any of the following conditions are met:
a. The metallic covering is impervious to moisture.
b. A lead sheath or moisture-impervious jacket is provided under the metal covering.
c. The insulated conductors under the metallic covering are listed for use in wet locations.


I am looking at a box of aluminum wound Southwire EZ-MC that says it has THWN conductors suitable for wet locations.

My question, with what rain tight connector?
You seen one? How does it stop the water inside the MC cable?

e57,
Conduit couplings are straight thread, and do not seal even when made up wrench tight. A compound such as required by 300.6(A) may help, but it is my opinion that rigid conduit couplings are less raintight than the old EMT couplings. I think that our couplings should have tapered thread like the plumbers couplings do. This would make them more water tight and provide a better fault clearing path.
Don

Here is some UL information
http://www.ul.com/regulators/raintight.cfm